Remote won't pair with Sony TV

Hi All,
New to the forum and already I have a problem. Got it all set up yesterday and the remote worked fine. Now today, it stopped working and won't pair up again. I have since replaced the batteries and rebooted the TV but still won't pair. Luckily my iPhone remote app still works so have been using that, but looking for any other remedies I could try before calling Sony. BTW, I have a 24" Sony NSX24GT1 model. Thanks!